The present invention relates to cable splices and, more particularly, to the various systems for splicing together different cable types heretofore requiring inter-cable isolation.
By way of background, an example of a procedure for interconnecting a filled (waterproof) cable with a gas pressurized cable is to splice a short section of air core cable, typically 20 feet long, to the end of the cable to be pressurized. Such short lengths are commonly called "STUBS" and are usually made with plastic insulated conductors. The stub is provided with an air dam which acts as a pressure plug to secure the pressurizing medium of the system to which it is attached. The opposite end of the stub from the end spliced to the pressurizeable cable is then spliced to the filled cable.
Each of the splices mentioned above is generally constructed by bringing the cable ends together within a splice case, a housing consisting generally of two semicylindrical shell parts with integral flanges that are brought together about the spliced cable ends over interposed end plugs to provide an hermetically sealed enclosure. The enclosure can then be pressurized or filled as necessary. The above mentioned installation, therefore, requires two such splice cases in addition to the stub.
When pulp insulated cables are involved the splicing system must take into consideration the fact that pulp insulated conductors are relatively quite fragile and readily subject to damage from repeated handling. They are also very susceptible to moisture pick-up if left exposed to the atmosphere, a factor which further increases the fragility. Consequently, such cables are routinely pressurized, and re-entry into splice cases containing pulp insulated conductors is avoided wherever possible. To facilitate reentry while minimizing the problem, some installation instructions recommend the use of a second stub and a third splice case in the transition from a pulp cable system to a waterproof cable. In such arrangement, the second stub is connected in series with the first stub with a second pressure dam located in the second stub. The third splice case is reenterable and located surrounding the splice between the two stubs. In such installations the use of a by-pass air pipe is recommended to pressurize the air core sections of the stubs between the pressure dams.
It is, therefore, an object of the present invention to provide a novel splice case that permits establishing a splice between dissimilar or incompatible cables entirely within the single case, eliminating both the need for stubs and additional splice cases.
Another object of the present invention is to eliminate a shortcoming of current practice which fails to preclude leaving a section of an air core stub unpressurized.
Another object of the present invention is to provide a more economical system for splicing together dissimilar or incompatible cables.
A still further object of the present invention is to provide a splice connection that requires much less time for initial installation and for post-installation servicing when repair or other entry is necessitated.